For anyone who's ever complained about having to take the extra step of putting on a chest strap to measure heart rate, it appears Garmin has been listening. With the introduction of the Forerunner 225, they join the small, but growing, group of GPS watch brands offering watches with optical sensors built in to measure heart rate from the wrist, rather than with a chest strap.For runners familiar with Garmin's other products, the 225 combines features from the popular mid range Forerunner 220 and the Vivofit to offer 24 hour data, whether you're working out or not. The built in activity tracker can tally steps taken and calories burned throughout your day, record your sleep, and send an alert reminding you to move if you've been inactive for more than one hour. On the fitness side, you'll have access to pace, distance, and calories burned throughout your run. If you're working out indoors, no need to use a foot pod the built in accelerometer will still calculate distance for you. The watch allows you to customize the full color screens as well as set up pace alerts and workouts, so you can set it up to see the information that's most useful to you. While some question the accuracy of wrist based heart rate because of inevitable inconsistencies in blood flow, Garmin's technology was designed to account for these changes while measuring light reflected and returned by your skin. To translate the measurement and make it easy to read mid workout for you, the watch displays color coded heart rate zones based on your max heart rate, calculated by subtracting your age from 220. When you're done working out, your workout will automatically upload to Garmin Connect if it's near your smartphone, so you can track your progress and have access to training plans and workouts. The 225's battery will last up to 4 weeks if you have it in watch mode, and up to 10 hours if you're using heart rate.